LED drivers are used in LED lighting fixtures to send power and/or control signals to one or more LEDs in the lighting fixture. Thus, LED drivers perform a critical role in ensuring that the LEDs operate in a manner that maintains reliability and performance. A buck converter is a type of LED driver. A buck converter is used in a control circuit at times to regulate direct current (DC) supplied to a LED circuit. Specifically, the buck converter may be a step-down DC to DC converter powered with rectified line voltage. A feedback circuit is used to regulate the duty rate of a regulating switch based on output current and input voltage.